One of the Absorption Lines of Hydrogen Has a Rest

question 1

Multiple Choice

One of the absorption lines of hydrogen has a rest wavelength of 656 nm (at rest means with respect to the observer, like in a lab) . You observe several stars and measure the wavelength of this same hydrogen absorption line in each star. Based on the measured wavelength of this line, which star is moving towards the Earth the fastest?

• A) 640 nm
• B) 670 nm
• C) 656 nm
• D) 630 nm
• E) 680 nm

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Definitions:

Unsystematic Risk

The risk associated with an individual asset or firm, which can be mitigated through diversification.

Covariance

A statistical measure that calculates the degree to which two variables move in relation to each other.

Correlation

The statistical measure of how two securities move in relation to each other, ranging from -1 to +1.

Risky Assets

Financial instruments that carry a higher degree of risk compared to risk-free assets, potentially leading to higher returns or losses.